Insulation systems for shielding high and low temperatures or for damping noise created in systems running at named temperatures, respectively, are dominated by mostly inorganic materials (glass or mineral fibre like Isover® or Rockwool®, foamed glass like Foamglas®, silica, silica gels like Aerogel® etc.) or rigid crosslinked expanded resins (PIR/PUR like Puren®, thermosets, such as melamine, like Basotec®, or phenolics). All those systems lack easy mounting and demounting properties, are in discussion due to fibre release, and show limits both when it comes to efficiently insulating bows, flanges etc., and of course can scarcely be offered as pre-insulation, e.g. on corrugated pipe. Furthermore fibrous materials and open-cell, rigid expanded resins have a high gas and water vapour transmission. This can e.g. cause condensation on the pipes which leads to corrosion. Foamed glass is not flexible and therefore the installation is quite elaborate and expensive. Due to this, foamed glass does not withstand vibrations, expansion/contraction cycles etc., limiting its fields of applications. Similar arguments are used against the other a.m. rigid insulations.
One of the major drivers for works in the field of more flexible high temperature insulation solutions definitely is the solar industry, especially since evacuated tube collectors showed up in the market, as their connected piping system may reach temperatures higher than 200° C. The majority of proposals for flexible high temp insulation bases on the use of a non-degradable or at least very temperature inert inner layer, such as in DE 19926850, EP 1239205 or in some applications in use (e.g. Trocellen Solar Sleeves, WIP-FLEX-TWIN® “V” etc.). However, all those solutions again have to rely on inner layers of the well-known inorganic kind and therefore show no significant improvement of the a.m. disadvantages of such materials. For low temperature insulation (below −30° C.) most of the a.m. rigid solutions are equally applied, showing the same disadvantages.
Flexible, means elastomeric, insulation materials unfortunately either will decompose at higher temperatures (120 to 200° C. depending on the polymer) and/or become brittle at low temperatures (−30 to −100° C. depending on the polymer). Some attempts have been made to support elastomeric or other sensitive polymer materials by equipping them with an inner structure or layer acting as spacer, such as in DE 9117159, in DE 4143670 and the very similar DE 4143646 and DD 247586 (all show corrugated structure), DE 2461013 (triangular structure), EP 1180635 (fibrous separator) etc., however, the materials used and the general construction will not allow to extend the use beyond +180° C. or −30° C. temperature limits, respectively. Especially high and low temperature insulation by using the same system is not feasible with the a.m. materials.